Meskernel LDK-40 Laser Range Sensor (40m) USB to TTL

The LDK-40 communicates via a standard 3.3V TTL UART serial interface. It includes an integrated USB-to-TTL converter. For Arduino connection, you can use the USB port directly for PC communication, or connect the module's TX/RX pins to a software serial port on the Arduino, ensuring you match the 3.3V logic level and baud rate as specified in the datasheet.

These settings control the sensor's measurement update rate. A 3Hz update consumes less power and is suitable for static measurements. 10Hz provides a balanced response for moderate-speed applications. 20Hz offers the fastest data output for dynamic, real-time tracking in robotics or automation, but may draw slightly more current. The setting is typically configured via a serial command.

The sensor operates at a nominal 3.3V DC supply. Its typical current consumption is under 60mA during active measurement. Ensure your power source can provide stable 3.3V power. The integrated USB interface can also supply power when connected to a computer or a 5V USB port with appropriate regulation.

Yes, the sensor uses a Class II red laser with a wavelength between 620–690nm and an output power of less than 1mW. Class II lasers are considered eye-safe for incidental exposure, but you should avoid staring directly into the beam. The low power also contributes to the module's overall low power consumption.

The measurement time typically ranges from 0.1 to 4 seconds, depending on target distance and reflectivity. Laser phase-shift sensors like the LDK-40 can struggle with transparent surfaces like glass or clear plastic, as most of the laser beam may pass through or reflect unpredictably, leading to inaccurate readings. For best results, target opaque, diffusely reflecting surfaces.